1. Field of the Invention
The present invention relates in general to a biomolecule detector and a detection method using the same. More specifically, the present invention relates to a biomolecule detector capable of detecting a biomolecule immobilized on a biomolecule chip based on the analysis of diffraction and/or refractivity of light transmitted through the biomolecule chip, and a biomolecule detection method.
2. Description of the Related Art
Recent technical advances in medical science and bioengineering have resulted in growing demands for a biomolecule detector in a broad range of applications including diagnoses of diseases, DNA typing, a forward genetic screen, pathogen detection, new drug discovery and development and so forth.
In general, a biomolecule detector consists of a biomolecule chip and peripherals of the biomolecule chip.
A biomolecule chip is a biological micro chip having biomolecules immobilized on a substrate. Biomolecule chips can be categorized based on the type of immobilized biomolecule, for example DNA chips, protein chips, etc. A biomolecule which is immobilized on a chip and binds with a target biomolecule in a sample is called a probe. Biomolecule chip-related technical fields in development include, for example: biomolecule immobilization techniques for immobilizing biomolecules on a substrate, techniques for binding immobilized biomolecules on a biomolecule chip with components of a sample, and biomolecule detection techniques for detecting the existence and the kind of biomolecules based on the analysis of a biomolecule chip where unknown biomolecules are immobilized.
FIGS. 1 and 2 illustrate a conventional biomolecule detection method and a biomolecule detector. In particular, FIGS. 1 and 2 show a biomolecule detection method and biomolecule detector using Laser-Induced Fluorescence (LIF) as the detection method.
In the LIF detection method, target biomolecules bind to or are labeled with a fluorescent substance. Target biomolecules are then mixed with a probe biomolecule immobilized on a biomolecule chip such that binding can occur between the target and probe biomolecules. Next, unbound (free) target biomolecules are removed, and light from a light source irradiates the biomolecule chip. Lastly, the amount of emitted fluorescence is measured and analyzed to determine the amount of target biomolecules that are bound to the probe biomolecules. A disadvantage of this method is that it requires a preprocessing step for labeling the target biomolecules with the fluorescent substance, which can result in contamination of the target biomolecules. Another disadvantage is that the method requires expensive, large equipment that is not readily portable.